In many standard punch presses, a punch element is carried on an upper turret in alignment over a die that is mounted on a lower turret. The punch and die are both held in circular tool holders. Before the press can be operated, the tool holders must be placed in vertical alignment with one another so that the punch and die are in turn in alignment during operation. An alignment tool previously used by the assignee of the present invention included upper and lower parts in which the upper part was provided with a pair of laterally spaced apart downwardly extending cylindrical pins that were placed in corresponding cylindrical openings in the lower part of the device to align the tool holders. The device was cumbersome to operate and there was no means of indicating when the upper and lower parts of the device were in alignment. Alignment tolerances were also not as good as are sometimes required. In addition, there was no device for progressively moving the upper and lower parts toward one another or for automatically bringing them into progressively better alignment with one another.
In some punch presses, because upper and lower turrets do not rotate on a common axis or for some other reason stations are out of alignment, the upper and lower parts of the alignment instrument should not contact one another while they are not able to be aligned.
In view of these and other deficiencies of the prior art, it is one object of the invention to enable upper and lower components of the alignment instrument to be placed into contact with one another only when they are in a position where they are capable of being aligned.
Another general object is to provide an improved alignment instrument that will align a punch and a die in three ways simultaneously; horizontally on perpendicular x and y axes with respect to the base of the punch press as well as automatically rotating the die with respect to the punch about a common vertical axis.
Another object of the invention is the provision of a device for moving upper and lower components of an alignment instrument apart or toward one another under the control of an operator for bringing them into alignment.
Yet another object of the invention is the prevision of an indicator that operates automatically to indicate the alignment of two components of the instrument which in turn align a punch holder with a cooperating die holder.
A still further object of the invention is the provision of an improved punch press alignment instrument having a visual display that will indicate both partial and complete alignment of components.
These and other more detailed and specific objects of the invention will be apparent in view of the following description and drawings which illustrate by way of example a few of the various ways the invention can be carried out within the scope of the appended claims.